1. Technical Field
The present invention relates to the field of international telecommunications call processing and, in particular, to method and apparatus for analyzing international long distance dialing errors and automatically completing a call if the error can be determined.
2. Description of the Related Art
Referring to FIG. 1A, there is shown a North American dialing plan for automatically accessing an international long distance telephone number without the assistance of an international operator. Most nations now have adopted certain international standards whereby one may access the foreign telecommunications network of a nation a caller calls without the caller's having to contact an international operator. In the United States, to obtain automatic international long distance access, one dials the digits 011 which comprise an international dialing access code IA. Other countries may adopt different codes, but the principle is still the same, the international dialing access code IA comprises a known code that distinguishes from intra-national (within the country) dialing codes such as those for accessing local and long distance services and assistance within the country.
Following the international access code IA, is a country code CO, the country code indicating the country or nation that the caller wishes to reach. Country codes used by international callers from the United States comprise two or three digits. Examples of country codes CO are 33 for France, 49 for Germany, 81 for Japan, and 972 for Israel. Again, this two or three digit country code is an agreed upon international country code that is used by callers all over the world to access a particular country adopting the standard.
If a country code comprises three digits, then, the maximum number of countries that can be dialed is one thousand. Since there are more than one thousand countries in the world, there is a requirement coming to increase the number of digits comprising the country code CO to four or more digits.
Following the country code, the caller frequently must enter a city code CI which may comprise one or two digits. Some countries do not require any city code, for example, Kuwait, which has a country code of 965 and does not require any city code. Thus, a minimum number of digits that can comprise a country code/city code combination is three digits. Examples may be Buenos Aires which has city code of 1 in Argentina. Argentina has a country code 54. So the combination for Buenos Aires, Argentina has three digits: 541.
In the United States and Canada and under the North American numbering plan, we call the city code CI an area code. Because of the great increase in demand for area codes in North America, it is contemplated that the "city code" or area code may, like the country code, exceed three digits and comprise four digits or more. Requirements in the United States that the area code have a middle digit of only a 0 or 1 have disappeared. Now an example area code may have the same three digits as the first three digits of a directory number.
The final step to dialing an international telephone number in the United States is to enter the local telephone number or directory number DN within the city and country desired. According to FIG. 1A, the local directory number DN typically comprises from 5 to 8 digits. On the other hand, as few as eight digits total including country code, city code and directory number (and excluding any international access code) may be required in some countries to complete a call to a directory number in that country.
In the United States and in foreign countries as well, there has been a considerable, almost an exponential growth, in the demand for new telephone numbers. Citizens no longer have just a telephone number for their residence telephone, they also may demand, for example, a telephone number for their portable cellular telephone, their pager, their personal computer and their facsimile machine. Foreign telecommunications carriers have to keep up with the demand by adding new city codes in a comparable mode to the way, in the United States, we have had to assign new area codes, for example, the new 732 area code in New Jersey. Also, the number of countries desiring to modernize their international dialing is fast approaching the one thousand level. It is difficult for telephone directories in the United States which provide international dialing instructions, let alone the international long distance service providers, to keep up with dialing plan changes necessitated by the demand for new telephone numbers. More and more, it is likely that a customer may refer to inaccurate sources for dialing information and, consequently, dial a number that may not be intelligible to the telephone network.
For example, France typically has a country code CO of 33 and the vicinity of Nice in France required a city code CI of 9. However, in order to increase the availability of telephone numbers in the vicinity, the French telecommunications network recently instituted the inclusion of a digit between the country code CO and the city code CI of 4. This digit must be included at location 2 in FIG. 1A. To further confuse matters, when one receives correspondence from one having a directory number DN in the vicinity, they are given the new directory number as, for example, 04 93 24 08 91. They may dial 33 04 93 24 08 91 by mistake, thinking that 04 is an accurate city code or they may dial 33 4 93 24 08 91; in other words, is the 0 in 04 necessary? The calling party may be confused by the instructions in their local telephone directory suggesting the entry of a country code and a one digit city code (the local directory may only identify the city code for Paris which is 1 and no other city codes). The caller may not know where the country code ends, the city code begins and ends and the directory number begins.
Referring again to FIG. 1A, at any one of locations 1, 2, 3 and 4, that is between the access code and country code, the country code and city code, between the city code and the directory number and in the directory number itself, there is an opportunity for a foreign telecommunications network to add new directory number capacity in a geographic region of the country by adding digits without deviating from the agreed-to international dialing plan.
Presently, when a caller in the United States tries to dial an international telephone number where the dialing plan has changed, the caller may receive no indication that there is a problem other than a prolonged "high and dry" period that may extend to a minute or longer where the caller, expecting to be connected, hears nothing. The high and dry condition can utilize national and international telecommunications resources for which no revenue will be obtained (and yet could have been used for other calls). Receiving such an indication, the caller may try again, then, receiving the same "high and dry" indication, try to reach their international operator, who may or may not be able to assist with the problem, depending on how well updated any database is that the international operator may have access to. Consequently, the international long distance carrier may suffer the tying up of an international operator for a period of time and obtain no revenue from the one or more call attempts. Moreover, each call attempt may tie up further local, international and foreign telecommunications facilities. Furthermore, the caller may be frustrated as they are not only unable to complete the call they want to but have no idea what the problem is. Of course, if the caller does take the additional step of calling an international operator for assistance and if the international operator is able to assist the caller, the international carrier providing the international operator services may be able to complete the call, but the international toll carrier may not be able to charge for the additional operator services because the international call completion failure was not the fault of the caller.
According to copending U.S. application Serial No., filed Aug. 27, 1997, there exists an opportunity under international dialing plans and standards to receive call value data providing some indication of why a call did not complete as dialed in the foreign country. For example, if the caller dials an invalid number, a cause code value of 28 is returned by the foreign network for "invalid number format. " Nevertheless, with such cause code value data, there is no provision for further automatically transmitting data that could be useful in updating a local database as to new foreign numbering plan changes. The present system only identifies a problem. Typically, changes to foreign dialing plans (adding digits at 1, 2, 3, or 4 in FIG. 1B) are handled "off-line" (not in real time). The foreign telecommunications carrier typically notifies the international carriers in the United States of changes in directory numbers and call routing so the changes can be made to their databases and call processing algorithms.
Consequently, there remains presently a problem with international calling plans and international dialing services that remains to be solved, the problem being that of assisting callers to reach the international telephone numbers they are trying to reach automatically and as efficiently as possible.